The Gotthard Base Tunnel is a railway tunnel through the Alps in Switzerland. It opened in June 2016 and full service began the following December. With a route length of 57.09 km (35.5 mi), it is the world's longest railway and deepest traffic tunnel and the first flat, low-level route through the Alps. It lies at the heart of the Gotthard axis and constitutes the third tunnel connecting the cantons of Uri and Ticino, after the Gotthard Tunnel and the Gotthard Road Tunnel.
Turnout at Faido multifunction station
Erstfeld, north portal, 460 m (1,510 ft) a.s.l.
Amsteg portal (maintenance access), 507 m (1,663 ft) a.s.l.
Sedrun portal (maintenance access, bridge over the Anterior Rhine), 1,334 m (4,377 ft) a.s.l.
A tunnel is an underground or undersea passageway. It is dug through surrounding soil, earth or rock, or laid under water, and is enclosed except for the portals, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube construction techniques rather than traditional tunnel boring methods.
Tunnel in Col du Galibier, France
Tunnel in Fort de Mutzig, France
Decorated portal to a road tunnel in Guanajuato, Mexico
Utility tunnel for heating pipes between Rigshospitalet and Amagerværket in Copenhagen, Denmark
